Patch: slapd's o_abandonmutex is unnecessary (ITS#1733)

Full_Name: Hallvard B. Furuseth
Version: HEAD (2002-04-08)
OS: Linux
URL: http://folk.uio.no/hbf/OpenLDAP/abandonmutex.txt
Submission from: (NULL) (158.36.148.34)
o_abandonmutex is only used to protect the single operation of
(re)setting or testing o_abandon. For such simple operations,
you can get the same effect just by declaring o_abandon as
`volatile sig_atomic_t'. Here is a patch.
rc is LDAP_SUCCESS (0) when I skip the assignment to rc in
back-ldbm/modify.c. Except for that, the patch is readable
without referring to the source.